Optical semiconductor device and method of fabricating the same

Abstract

An optical semiconductor device includes a laminated layer structure, an intermediate film formed on an end surface of the laminated layer structure, and a passivation film formed on the intermediate film. The passivation film has a quantity of ion projection than that of the intermediate film.

What is claimed is:  
     
       1. An optical semiconductor device comprising: 
       a laminated layer structure;  
       an intermediate film formed on an end surface of the laminated layer structure; and  
       a passivation film formed on the intermediate film,  
       the passivation film having a quantity of ion projection larger than that of the intermediate film.  
     
     
       2. The optical semiconductor device according to  claim 1 , wherein the intermediate film comprises a film formed by ion-assisted deposition. 
     
     
       3. The optical semiconductor device according to  claim 2 , wherein the intermediate film and the passivation film have a constant quantity of ion projection from an ion source, and the intermediate film has a rate of growth higher than that of the passivation film. 
     
     
       4. The optical semiconductor device according to  claim 2 , wherein the intermediate film has a quantity of ion projection from the ion source smaller than that of the passivation film. 
     
     
       5. The optical semiconductor device according to  claim 1 , wherein the intermediate film has not been subject to ion projection. 
     
     
       6. The optical semiconductor device according to  claim 1 , wherein the intermediate film and the passivation film are made of aluminum nitride, and the intermediate film has a refractive index larger than that of the passivation film. 
     
     
       7. The optical semiconductor device according to  claim 1 , wherein the passivation film is made of aluminum nitride, and the intermediate film has no nitrogen. 
     
     
       8. The optical semiconductor device according to  claim 1 , wherein the intermediate film and the passivation film are made of aluminum nitride, and have different conditions for film growth. 
     
     
       9. The optical semiconductor device according to  claim 1 , wherein the intermediate film is 3 nm thick or thinner. 
     
     
       10. The optical semiconductor device according to  claim 1 , wherein the intermediate film is 1 nm thick or thinner. 
     
     
       11. The optical semiconductor device according to  claim 1 , wherein the optical semiconductor device receives or emits light via the end surface. 
     
     
       12. The optical semiconductor device as claimed in  claim 1 , wherein the passivation film is a film formed by ion-assisted deposition. 
     
     
       13. The optical semiconductor device as claimed in  claim 1 , wherein the passivation film is a film formed by ion-assisted deposition and the intermediate film is a film formed by ion-assisted deposition. 
     
     
       14. The optical semiconductor device as claimed in  claim 1 , wherein the passivation film is a film formed by ion-assisted deposition and contains a component that is an ionized component in the ion-assisted deposition.